Updating some iOS devices (iPhone 5s and earlier and iPad Air and earlier) to iOS 9.3 can require entering the Apple ID and password used to set up the device in order to complete the software update. If you can't recall your password or can't sign in, try these steps.
In some cases, the hint that you see on the Activate iPhone screen might not match your current Apple ID. To make sure that you're entering your Apple ID information correctly, try these steps: See the Details here ...
